Question

greenhouse gases emitted into the atmosphere capture heat and warm earth’s surface with some greenhouse gases having much greater heat-trapping capacities than others.
which is the most potent greenhouse gas emitted by human activities?
○ carbon dioxide
○ methane
○ halocarbons
○ nitrous oxide

Explanation:

To determine the most potent greenhouse gas from human activities, we analyze each option:

• Carbon dioxide ($\ce{CO_2}$) is a major greenhouse gas but not the most potent in terms of heat - trapping capacity per molecule.
• Methane ($\ce{CH_4}$) has a relatively high heat - trapping capacity, but halocarbons (like CFCs, HFCs etc.) are more potent. Halocarbons are synthetic compounds and have very high global warming potentials (GWP) compared to methane and carbon dioxide. Nitrous oxide ($\ce{N_2O}$) also has a high GWP but is less potent than halocarbons in terms of heat - trapping per molecule over a given time period when considering human - emitted greenhouse gases.

Answer:

C. halocarbons